The threat of the “fiscal cliff” has sunk in — in the minds of the public, that is.

Most people surveyed say the impact of going over that cliff — the threat of automatic spending cuts combined with across-the-board tax increases at year’s end, unless Congress finds another course — would be “mostly negative for the economy” as well as for their own personal financial situation.

Six in 10 say so on both counts, in a Pew Research Center/Washington Post survey.

The public also is skeptical that President Barack Obama and congressional Republicans will reach an agreement by the end of the year . About half — 51 percent — say the two sides will not reach an agreement, while just 38 percent say they will.

People are poised to blame Republicans more than the president for failure: — 53 percent say Republicans will carry the responsibility for failure, if they do, compared with 29 percent saying Obama will bear the blame.